High specific surface area niobium-doped tin oxide nanoparticles produced in spray flames as catalyst supports in polymer electrolyte fuel cells

Flame-Made Ir–IrO2/TiO2 Particles as Anode Catalyst Support for Improved Durability in Polymer Electrolyte Fuel Cells

“…For these measurements, a reversible hydrogen electrode (RHE) and platinum were used as a reference electrode and a counter electrode, respectively. The procedure of Pt deposition has been described in our previous paper. , Briefly, a certain amount of Ir–IrO 2 /TiO 2 particles was dispersed in a mixture of ultrapure water and ethanol in a flask placed in an oil bath with stirring for 30 min. Subsequently, a platinum chloride solution (Tanaka Kikinzoku Kogyo Co., Ltd.) was added to the mixture and stirred for 60 min.…”

“…The flame aerosol process is a simple and versatile method for synthesizing nanostructured particles in the gas phase with a high production rate from the laboratory to the industrial scale. − It can also be used for the production of metal-loaded metal oxide particles. The flame aerosol process offers the advantages of a single-step and continuous process, less time-consuming, a large temperature gradient, and high productivity. − This method allows synthesizing high-purity metal oxide nanoparticles with unique morphologies, − such as chain-like structures, close-packed aggregated network structures, necking structures, ,,, and fused-aggregated network structures. , These network structures of particles improve the conductivity and reduce the amount of usage of precious metals such as Pt, Ir, and Nb. Furthermore, the flame aerosol process can be used to synthesize metal-loaded metal oxide particles with low concentrations of precious metals.…”

Porosity Engineering of Pt-Loaded Nb-SnO2 Catalyst Layers in Polymer Electrolyte Fuel Cells

“…34 In our previous study, we found that MEAs with Pt/NTO catalysts fabricated using the hot-press method have densely packed catalyst layers and lower porosity than conventional carbon supports. 20 Current− voltage (I−V) measurements show that�compared to a carbon support�an NTO support exhibits both a voltage drop in the high-current region and increased gas-diffusion resistance. The presence of pores within the catalyst layer is critical to its effectiveness, acting as channels through which reactant gases access the catalytic interface.…”

“…The use of spray combustion, in which the precursor solution is burned directly, promotes gasification of the precursor and enables uniform deposition of Pt nanoparticles on the NTO particles. In addition, NTO nanoparticles with high specific surface areas have been prepared by adjusting the combustion conditions, and the fuel cell properties were determined using a single cell …”

“…In addition, NTO nanoparticles with high specific surface areas have been prepared by adjusting the combustion conditions, and the fuel cell properties were determined using a single cell. 20 The main component of a PEFC is a membrane−electrode assembly (MEA) consisting of a polymer−electrolyte membrane and a porous electrode coated with catalysts, which performs hydrogen oxidation at the anode and oxygen reduction at the cathode. Conventionally, catalyst electrodes are hot-pressed onto both sides of a proton-exchange membrane at high pressure and relatively high temperature (i.e., using the hot-press technique).…”